1. Field of the Invention
The present invention relates to a non-contact running type elevator in which a car is run in non-contact with guide rails.
2. Description of the Related Art
In general, a car of an elevator is supported on a pair of guide rails which are vertically disposed in the elevation path, and the car is elevated by ropes which are wounded around a hoister. At this time, shaking of the car, which occurs due to imbalance of the load weight or movement of passengers, is suppressed by the guide rails.
As a guide apparatus for guiding the car, use is made of roller guides comprising wheels, which are in contact with the guide rails, and suspensions, or guide shoes which slide over the guide rails and guide the car. In this contact-type guide apparatus, however, vibration or noise occurs due to misalignment of guide rails or joints of the guide rails. In addition, noise occurs when the roller guides rotate. Thus, there occurs a problem that the comfortablility of the elevator deteriorates.
In order to solve this problem, there has conventionally been proposed a method of non-contactly guiding the car, for example, as disclosed in Patent Documents 1 and 2.
In Patent Document 1, a guide apparatus comprising electromagnets is mounted on the car, and magnetic force is caused to act on iron-made guide rails, thereby non-contactly guiding the car.
Patent Document 2 discloses the use of permanent magnets in order to solve problems, such as a decrease in controllability and an increase in power consumption, which occur in the structure using the electromagnets.
Patent Document 1: Jpn. Pat. Appln. KOKAI Publication No. H5-178563; and
Patent Document 2: Jpn. Pat. Appln. KOKAI Publication No. 2001-19286.